Clinical Outcomes Associated with Complex Infection in Patients with Cystic Fibrosis.

Little is known in contemporary cystic fibrosis (CF) cohorts about the outcomes after new species infections. To evaluate the changing epidemiology and clinical outcomes associated with species infections in persons with CF. A cohort study of children and adults with CF was conducted from 1997 to 2018 in Toronto, Canada. Patients were characterized as those with no history of species infection and as those who were culture-positive for species for the first time in this time frame and were categorized by species (. , , , or other) and strain ( ET-12). Cox models were used to estimate the risk of death or transplantation. Mixed-effects models were used to assess the impact of species on odds of pulmonary exacerbations and effect on lung function (percentage predicted forced expiratory volume in 1 second [FEV]). A total of 1,196 patients were followed over 20 years; 88 patients (7.4%) had one or more culture-positive for species. Patients with ET-12 infection had a median time to death of 1.95 years compared with 5.30-6.72 years for those with other infections. ET-12 infection was associated with a greater risk of death or transplantation compared with patients with no history of infection in a univariate model (hazard ratio, 3.92; 95% confidence interval 2.25-6.81) but was no longer significant after adjusting for confounders. Pulmonary exacerbations were more common in those with infections and remained significant in the ET-12 group after adjusting for confounders (odds ratio, 2.96; 95% confidence interval, 1.17-7.53). No differences were noted in baseline FEV% or the rate of FEV% decline between the groups with and without species infection. With the exception of ET-12, the acquisition of species infection did not appear to worsen clinical outcomes compared with those with no history of infection. Given this, prognosis, management and clinical trial inclusion protocols may need to be reevaluated for persons with infection.